Ignition apparatus



April 17, 1945- vW. J. SPENGLER A 2,373,981

IGNITION APPARATUS Filed July. 7, 1942 INVENTOR fr ATTORNEY ing drawings.

Patented Apr. 17,1945

`IGNITION APPARATUS Walter J, Spengler, Sidney, N. Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application July 7, 1042, Serial No. 450,043

16 Claims. .(Cl. 171-209) This invention relates to ignition apparatus and more particularly to` supercharged ignition devices and pump means therefor.

One object of the present invention is to pro-` vide a novel combination of-pump means in a magneto generator to supercharge the casing ,thereof and particularly the distributor chamber. 1

Another object is to provide a novel air pump adopted for use in the above combination and having one or more reciprocating pumping members actuated in a novel manner by a rotating member..

A further object is to the above character with novel means for effect- 'ing intake and delivery of the air.

Still another object is to provide a light rugged pump structure .which is compact and comprises a small number of readily assembled parts.

A still further object is to provide a novel unitary pump apparatus eiciently operable as a supercharger and adapted to Ibe mounted in a novel manner ina magneto generator or other ignition device so as to be removable as a unit for replacement or repair without impairing the operation of the magneto under normal atmospheric conditions.

The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same isread in connection with the accompany- It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a deiinition of the limits of the invention, reference for this latter purpose being primarily had to the appended claims.

In the drawing, wherein like reference characters refer to like parts throughout. the several views,

provide an air pump of I' Fig. 1 is a view in elevation, with parts broken away and shown in section, of one form of magneto embodying the present invention; and

Fig. 2 is a sectional view taken substantially along line 2-2 of Fig. 1f.

'I'he invention is illustrated in the drawings, by

way of example, in the form of a novel pump mounted within a casing of a magneto adapted for use in the ignition system of an internal combustion engine. In the form shown, the pump means is driven by the ignition distributor shaft and is adapted to deliver air under pressure to theV distributor. chamber of the magneto. By thus maintaining the air within the distributor chamber under pressure, danger of undesirable arcing within said chamber and, hence, failure of the ignition system at high altitudes are substantially eliminated,

One form of the pump means of the present invention is shown operatively mounted for supercharging the distributor chamber II) of a magneto generator II` of the type disclosed in my Patent No. 2,104,140. It is to be understood that the pump may also be utilized, for example, for supercharging the entire magneto interior or compartments thereof other than the distributor chamber and may be embodied in other ber IIJ from a compartment I5 which contains magneto rotor I6. For the purpose of reducing leakage from chamber I0 so that air under pressure might be maintained therein or, if desired, to render said chamber substantially air or duid-tight, the parts 4comprising the walls thereof are carefully iitted together to produce substantially air-tight junctions therebetween. However, to further insure against excessive leakage of air, it may be desirable to employ gaskets or apply a suitable sealing composition having a high melting point, such as hydrolene wax at the engaging surfaces of the parts.

Mounted in wall I2 is a bearing Il which journals a hollow distributor drive shaft I8 having a flange I9 formed. therewith, said flange having a distributor rotor 20 suitably attached thereto, for example, ,by screws 2|. Sockets 2Ia are preferably molded in said rotor to receive screws 2l and each of said sockets preferably projects beyond the face of the rotor so that an air gap 2Ib is provided between said rotor and the -anged end of shaft i8. Rotor 20 carries a central contact 22 and a contact 23 near the periphery which are connected to each other, the former engaging a current supply contact 24 in insulating block I3 and the latter cooperating in a` the art to distribute high tension current from the secondary winding of the magneto coil to the engine spark plugs.l

The left-hand end of shaft I8, as viewed in Fig. 1, projectsfbeyond wall I2 and a gear wheel 26 is keyed or otherwise fixed to the projecting portion of said shaft, said vgearwheel being in driving mesh with a gear on rotor shaft I6. These driving means are enclosed in a compartment 21 formed by a cup-shaped cover 28 which is secured to wall I2 and forms a part of the mag` neto housing. A portion of shaft I8 adjacent flange I9 has a close running fit with a portion I2a of wall I2 to minimize any leakage of air v from chamber II! sothat the latter may be substantially air-tight.

In order to maintain the pressure of. the at- .mosphere in chamber I above atmospheric pressure outside of said chamber, means are mounted in magneto Il for compressing air admitted thereto from outside the magneto and discharging the compressed air into said chamben As shown, said means comprise a cylindrical casing 30 open at one end and provided with an external ange 3I at theother end whereby said casing is secured in cover 28, for example, by screws 32, with the open end thereof extending into compartment 21. ICylindrical casing 30 thus completes and maybe considered as a part of the enclosing housing for the illustrated ignition apparatus.` The central axis of the cylindrical wall 30a -of casing 30 is eccentric with respect to the axisI of'hollow distributor shaft posed portion rl(ma, with the periphery of shaft '33, the end of said portion being located in the III same transverse plane as ports 38 in `order to successively overlap the latter during each revo:

' In operation, rotation of rotor 34 in acounterclockwise direction, as viewed in Fig. 2, causes `plungers 31 to move radially outward in response to centrifugal forcei into engagement with the internal periphery of casing wall 30a, the eccentricity of' which causes reciprocation of said v plungers in bores 36. lWhen port 38 connects i I with intake passage 33 during rotation of said rotor, air intake at atmospheric pressure begins and continues until passage 39 moves beyond port 38. Passage 39 preferably has portion 39a thereof so located relative to housing wall a that airintake' begins as the plunger 31 -is moving voutwardly in bore 36 and is substantially at its outermost or bottom dead center position, thereby permitting a maximum volume of air tobe admitted into bore 36.-- The' lower piston, as shown in Fig. 2, is at its outermost position and intake has just ceased. Compression begins when port 38 movesout of communication 'with passage -39 and continues until said port overlaps I8 and a stationary stub shaft 33 is rigidly sev cured to the casing,` preferably by being formed integrally therewith, said stub shaft being coaxial with and extending into the interior of said' -suitable means, such as by cooperating splines.

Rotor 34 is provided with one or more radial,

cylindrical bores or recesses 36, two being shown in the present embodiment, each of which is ydischarge passage lill,l at which point piston -31 is substantially at its topdead center or innermost position, having effecteda maximum compression of the air which is then discharged into chamber I0 through-'passages 40, 40a and shaft I8. This cycleof operations is repeated by each plunger 3T during every. revolution of rotor 34, thereby maintaining relatively continuous -o e of' air under pressure into chamber I0.

It is to be noted that the novel pump means, as shown, comprise onlythree movable Darts, all of which arerelatively simple in design and con` struction, and thatthe pump'can be removed from its housing without affecting the connection..

between distributor rotor 20 and thel drive means therefor and Without' altering the normal operation oi the magneto except for the supercharg" ing of chamber I0. If desired, light springs may be used to assist centrifugalaction in moving plungers 31-outwardly. l

There isthus provided a novel combination of parts wherein means are mounted in the casing of an ignition device and driven thereby to superl charge the interior of said'casing. There is also provided novel pumpmeans adapted for super.

`adapted to receive a cylindrical plunger or pis j ton- 31, the latter preferably having the outer end thereof rounded for smooth engagement with 5 the internal periphery of Wall 30a. The inner end of each of said bores terminates a short dis. tance from the inner wall of rotor 34 and a passage or -port'38 (Fig. 2) connects each of the bore interiors to the central recess of said rotor which receives extension or journal 33.y The .latter is provided with a.- central axial intake passage 39 which communicates at one,e'nd with the magneto exterior and at the other end, by'means of an angularly disposed portionv39a, with the periphery of journal 33. The open end-.of portionA 39a of said passage-isalocated inthe same transv verse plane as each of ports 38 and subtends a substantial 'angular distance around said shaft, preferably about 90, so that each of ports 38 is in communication .with intake passage 39 for. approximately one-fourth of each revolution of rotor 34. A lcentral axial discharge passage 40 is also provided in journal shaft 33 and connects at one end with the interior of'shaft I8 and at the other end, by means of an singularly dis- A parts.

charging the distributor chamber of a magneto generator, said pump being compact, positive in operation and comprising a'minimum of moving A novel arrangement for mounting said pump in the magneto in relation to the .l distrib- I* utor rotor'and the. drive means for said rotor is also provided as well as novel means for controlling` the air intake and discharge of the pump.

Although only a single embodiment of the invention has `been illustrated and described, it is to be expressly understood that the same is not limited thereto. For example, it will novvbev apparent to'those skilled in the art that three or more equally' spaced bores containing plungerstherein could beused instead of the two illustrated. Various other changes may also be made in the design and arrangement of parts illus-l trated.v without departing from the spirit and scope of vthe invention. For a definition of the limits of the invention, reference ily-to the appended claims.

What is claimed is: Y 1. In an ignition device, acasing and means i for supercharging said casing comprising a cylinis had primar- Y drical housing mounted in said a rotor veccentrically mounted in said housing,- said rotor having at. least one radial bore, a plunger slidably mounted in said bore and lhaving its outer vits bottom dead center position and said discharge'passage connecting with said port When said plunger is approximately at top dead center position.

2, Ina magneto having a housing and a substantially duid-tight chamber in said housing containing an ignition distributor, a drive shaft for the rotatable part of said distributor, a pump mounted in Said housing and drivably connected to said shaft, and means 4controlling the air intake and discharge of said' pump, said last-named means comprising an air intake passage communicating with the housingy exterior and a discharge passage. connecting with said chamber through an axial passage in said shaft. f y

3. In a magneto having a housing and a substantially air-tight chamber in saidhousing 'containing a distributor. a drive member directly connected to the rotary 'element of said distributor, an air pump mounted in said housing and having a moi/able part thereof directly connected to said drive member, and means controlling the air intake and discharge o f said pump, said means comprising an intake passage communicating with the housing exterior and agdischarge passage connecting with said chamber- 4. In4 pump apparatus adapted for.. supercharging an ignition device, means yforming a under pressure into said chamber through a passage in said drive means.

8. hi a magneto having ,a housing and a substantially fluid-'tight chamber in said 'housing containing an ignition distributor, a drive shaft means including a hollow shaft for said discompression chamber, including a reciprocating plunger, a cylindrical casing eccentrically surrounding said means, said lplunger engaging said casing, drive means for rotating said first-named means whereby said plunger is reciprocated, andv means including a plurality of passages for controlling the. intake and discharge of said compression chamber., y

5, In apparatus of Ithe class described, a yhousingfa member' eccentrically mounted relative to said housing and having a radial bore therein, a plunger slidably mounted in saidbore and having its outer end adaptedior engagement With Asaid housing. in such a manner that relative rotation between said member and said housing reciprocates 'said plunger, and means connecting with said bore and adapted to control the admission of air' thereto and discharge of air therefrom.

6. Pumping means comprising a. rotary anember, atl least one centrifugally responsive plunger slidably mounted in .said member to eect air compressionfwhen reciprocated, a housing eccentrically disposed relativev to said member and` adapted toxengage said plunger, and lmeans for effecting rotation of'said member relative 'to said housing to cause reciprocation of said plunger.

l `7. In a magneto having a' substantiallyuidtight chamber, a distributor in said chamber and 'drive means extending' through the wall of said chamber for connection with the rotorof said distributor,r the combination with said drive means of a pump connected to said drive means and actuated thereby,lsaid pump being disposed on the tributor and a supercharger pump connected to said shaft to be actuated thereby, said supercharger pump discharging air under pressure into said chamber through said hollow shaft.

' 10. In apparatus of the class described, a substantially fluid-tight chamber, a distributor rotor in said chamber, a hollow drive shaft extending through the wall of said chamber and connected at one/ end thereof to said distributor rotor, a pump rotor connected to the other end of said shaft, plunger means in said pump rotor for compressing air, an eccentric surrounding said pump rotor and adapted to engage and actuate said plunger means, and a member rigidly secured to said eccentric and extending centrally through said pump' rotor as a journal therefor, said member having an inlet passage, for directing air to said plunger means for compression and a discharge passage for directingv the compressed air from said plunger means to the interior of said shaft.

11. In apparatus ofthe class described, a housing having a substantially fluid-tight chambena distributor rotor in said chamber, a hollow vdrive shaft extending through the wall of said chamber andconnected at one end thereof to said distributor rotor, a pump rotor connected to the other end: of said shaft, plunger means in saidv pump 4rotor for compressing air, an eccentric surrounding having a relatively duid-tight chamber, a

exterior of said chamber' and-discharging air 75 driven member in said chamber, drive means extending through the Wall ci said chamber and connecting at one end with said driven member, a

pump rotor connected at'the otnerend of said shaft, plunger means in said pump for compressing air, an eccentric surrounding said pump rotor and adapted to engage and actuate said plunger means, and means for directing air to said plunger. means for compression and for directingthe compressed air lfrom said plunger means to said chamber.

13. An electric 'ignition apparatus for any air? plane which is adapted to y in rarifled atmospheres including a substantially air-tight enclosing casing for said ignition apparatus, means for connecting said-enclosing casing with atmosphere outside said enclosing casing, and pressureV increasing means within said enclosing casing, said pressure increasing means having its intake; side in connection with `said communicating means so that upon actuation of said' pressure increasing `xmeans said apparatus within said casing will be ksupercharged to a pressure substantially higher than the pressure of atmosphere outside said casing 14.A An electric ignition apparatus for an air- -plane which is. adapted to fly in raried atmos pheres including a magneto, a distributor, a' sub. stantialy air-tight enclosing casing for said. distributor, means for connecting said enclosing .casing with atmosphere'outside saidl enclosing casing,

and pressure increasing means Within saidenclosf ing casing,.said pressure increasingmeans having. its intake side in connection with said communieating means so that upon actuation of said pressure increasing means said apparatus within said casing will be supercharged to a pressure substan= tialy' higher than that'of the atmosphere outside saidv casing. I I

15. An ignition device including a rotatable shaft, a substantially air-tight enclosing casing for said device, a port in said casing, pressureincreasing means Iwithin said-enclosing casing, said pressure increasing means'havingits intake side in substantially air-tight communication with said port, and means for .actuating said pressure increasing means .fromsaid shaftso, that' uponA rotation thereof the pressurenvithin said device enclosing casing will be .built up ftoa valuesubz stantially higher than. the pressurexoutsidelsaid enclosing easing. Y 16. A magneto distributor device including a rotatable shaft, a substantialy air-tight enclosing casingffor said device, a port in'said casing,pres i f sure increasing means Within said enclosing casing, said pressure increasing means having its intake side in substantially air-tight communication with said port, and means for actuating said pressure increasing means through said shaft so that upon rotation thereof the pressure within said device enclosing casing will be built up lto a value substantially higher than the pressure outside said enclosing casing.

i WALTER .I SPENGLER 

